5.3: Experience-dependent plasticity
- Page ID
- 198002
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Experience-dependent plasticity involves changes in existing neural circuits that occur in response to specific learning experiences that vary across individuals. In contrast to experience-expectant plasticity, experience-dependent plasticity is not constrained to specific developmental periods; thus experience-dependent changes facilitate learning throughout life, although plasticity tends to be most pronounced in childhood (Fu & Zuo, 2011). This enhanced plasticity during development allows neural structure and function to be influenced by lived experiences that occur during early childhood (Kolb & Gibb, 2014), potentially shifting longer-term developmental trajectories. [1]
Involves changes in existing neural circuits that occur in response to specific learning experiences that vary across individuals. Experience-dependent plasticity is not constrained to specific developmental periods; thus experience-dependent changes facilitate learning throughout life, although plasticity tends to be most pronounced in childhood
Experience-dependent learning involves the selective strengthening of particular synaptic connections in response to experience as well as the elimination of others that are under-utilized or inefficient (Kolb & Gibb, 2014; Takesian & Hensch, 2013; Trachtenberg et al., 2002). These changes occur in the specific neural circuits that encode and process particular experiences. In other words, the type of experience determines the specific neural circuits involved in the experience-dependent change. This has been demonstrated in diverse domains ranging from music and sports training to language learning and meditation (Dayan & Cohen, 2011; Gotink et al., 2016; Hyde et al., 2009; Kraus & Chandrasekaran, 2010). Across domains, the intensity and duration of environmental experiences influence the degree of neuroplasticity and learning that occurs (Dayan & Cohen, 2011; Gourevitch, Edeline, Occelli, & Eggermont, 2014; Kolb & Gibb, 2014; Kraus & Chandrasekaran, 2010). As an example, some children hear more language than other children and this natural difference in language exposure, when compounded over time, is associated with differences in the structure and function of language-related brain areas (Romeo et al., 2018a; Romeo et al., 2018b). [1]
The ability of the nervous system to change its activity in response to stimuli by reorganizing its structure, functions, or connections
Let’s take a moment and think about how experience-dependent plasticity applies to infant and toddler brain development. Children’s brain development reflects an adaptation to their lived experiences (Johnson, Jones, & Gliga, 2015; Nketia, Amso, & Brito, 2021). Take for instance how the lived experience of family socioeconomic status (SES) can impact brain development. From a child development perspective, SES is a multidimensional construct, often combining parent's education, occupation, and income (McLoyd, 1998). During the prenatal period, family SES has been associated with fetal (Lu et al., 2021) and neonatal (Spann et al, 2020; Triplett et al., 2022) brain structure. During infancy, SES has been associated with differences in brain structure and development (Betancourt et al., 2016; Hanson et al., 2013) and functional connectivity (Gao et al., 2015; Ramphal et al., 2020). For example, higher SES has been associated with greater cortical (e.g., in the frontal and parietal lobes) and subcortical gray matter volume in infants (Betancourt et al., 2016; Hanson et al., 2013). In children and adolescents, higher SES has been repeatedly linked with larger hippocampal volume (Farah, 2017). [3] [4] [5]
A multidimensional construct, combining factors such as an individual's (or parent's) education, occupation, and income
Located immediately behind the frontal lobe, and is involved in processing information from the body’s senses
Brain tissue primarily composed of cell bodies and dendrites
Located in the forward part of the brain, located behind your forehead and is involved in reasoning, motor control, emotion, and language
While family SES has been found to be associated with developmental differences in children’s brain structure and function, there is considerable debate as to whether growing up in poverty causes differences in early brain development, or whether poverty is merely correlated with other factors that are the true cause of early differences (Farah, 2018). A randomized control trial shows that a predictable, monthly unconditional cash transfer given to low-income families for one year may have a causal impact on infant brain activity (Troller-Renfree et al., 2022). Figure \(\PageIndex{1}\): showcases some of this data using topographic heat maps from one year old infants. These topographic heat maps display the distribution of power across the scalp for both groups in the study (high cash–$333 per month versus low cash–$20 per month) in each frequency band (theta, alpha, beta and gamma). Warmer colors represent more power in each respective frequency band. “Power” refers to the amount of brain activity in a certain frequency band, broadly reflecting the electrical activity of the underlying brain. Power varies across frequency bands and between people. “Absolute power” refers to the amount of brain activity measured within a certain frequency band. [6]
When you look over Figure \(\PageIndex{1}\) and compare the heat maps for the high-cash and low-cash groups, what differences do you notice? An important distinction to notice is that the high-cash gift group appears to show more beta-power and gamma-power relative to the low-cash gift group. These differences in brain activity patterns are important because research associates them with developmental differences. For example, more absolute power in mid-to-high (i.e., alpha, beta, and gamma) frequency bands has been associated with higher language (Benasich, Gou, Choudhury, & Harris, 2008; Brito et al., 2016; Gou, Choudhury, & Benasich, 2011; Maguire & Schneider, 2019), cognitive (Benasich, Gou, Choudhury, & Harris, 2008; Williams et al., 2012), and social-emotional (Brito et al., 2019) scores, whereas more absolute or relative low-frequency (i.e., theta) power has been associated with the development of behavioral, attention, or learning challenges (Barry, Clarke, & Johnstone, 2003; Harmony et al., 1990; McLaughlin et al., 2010). [8]
The poverty-reduction randomized controlled study is a great example of experience-dependent plasticity at work. Higher cash transfers changed a child’s (and their family’s) experiences enough to lead to changes in infant brain development. While we, as caregivers of infants and toddlers, may not be able to provide cash transfers to families, there are other things we can do, through our everyday interactions with children, to positively impact their brain development.
Attributions:
- [1] Ellis et al., (2022). Why and how does early adversity influence development? Toward an integrated model of dimensions of environmental experience. Development and Psychopathology, 34(2), 447-471. CC by 4.0
- [2] Image from Nelson et al., (2019). How early experience shapes human development: The case of psychosocial deprivation. Neural plasticity, 2019,1676285. CC by 4.0
- [3] Troller-Renfree et al., (2022). The impact of a poverty reduction intervention on infant brain activity. Proceedings of the National Academy of Sciences, 119(5), e2115649119. CC by 4.0
- [4] Brito & Noble (2014). Socioeconomic status and structural brain development. Frontiers in Neuroscience, 8, 276. CC-BY
- [5] Nolvi et al., (2023). Prenatal stress and the developing brain: Postnatal environments promoting resilience. Biological Psychiatry, 93(10), 942-952. CC by 4.0
- [6] Troller-Renfree et al., (2022). The impact of a poverty reduction intervention on infant brain activity. Proceedings of the National Academy of Sciences, 119(5), e2115649119. CC by 4.0
- [7] Image from Troller-Renfree et al., (2022). The impact of a poverty reduction intervention on infant brain activity. Proceedings of the National Academy of Sciences, 119(5), e2115649119. CC by 4.0
- [8] Troller-Renfree et al., (2022). The impact of a poverty reduction intervention on infant brain activity. Proceedings of the National Academy of Sciences, 119(5), e2115649119. CC by 4.0